When Gillian White first applied to be a Games Maker a couple of years ago, she didn't tell anyone what she had done. Despite being an "optimistic" person, she says, "there was this part of me that thought, I hope it's not going to be awful – and if it's awful, do I really want people to know I was there?"

Her time at the Olympic Park, working as a volunteer "brands enforcer" alongside trading standards, put paid to any such fears. On Monday, White will be among 14,000 Games Makers, soldiers, ceremony performers, emergency service personnel and London schoolchildren who will be honoured with the best seats in the house for the athletes' victory parade through the capital, as a thank you for their part in creating what the retailing consultant now cheerfully describes as one of the most memorable experiences of her life.

Up to 700 British Olympic and Paralympic medal winners will be transported along a three-mile route from Mansion House in the City to Buckingham Palace in a caravan of floats and open-topped buses, the centrepiece of a celebratory parade expected to be witnessed by hundreds of thousands of spectators.

The final section of the route, however, from Trafalgar Square along the Mall to the palace, will be closed to the public, with access only to a small proportion of those who, in the description of Lord Coe, have helped "make the Games great".

For White, who like many of her fellow volunteers plans to wear her Games Maker uniform for one last time, the chance to watch the parade from the Mall represents "a final hurrah" to round off her Olympic experience. "It shows what we did was really valued. It's so rare in life that you get moments where people say to you: 'I'm really proud of you.' Nobody has said that to me since I was about five and managed to swim across the swimming pool."

While the final number of athletes taking part is yet to be finalised, the mayor's office, which is co-ordinating planning of the event, said it expected over 90% of medal-winners to participate, with the athletes Mo Farah and Jessica Ennis, cyclists Chris Hoy and Victoria Pendleton, sailor Ben Ainslie and triathlon gold medallist Alistair Brownlee among those who had confirmed their attendance. Most Paralympic medallists are also expected to take part.

The athletes will be transported in 21 floats, arranged alphabetically by sport, each carrying about 40 Olympic and Paralympic athletes, who will travel together in a procession that is expected to take 15 minutes to pass a fixed point. They will be preceded by a specially commissioned carnival group fronted by two giant lion heads.

The occasion has inspired the mayor, Boris Johnson, to uncommon rhapsodies, in which he hailed "a glorious miasma of colour, noise and excitement" and predicted a ceremony equal to any staged to welcome ancient Olympians, marking the achievements of athletes "whose names and triumphs will live on for centuries to come".

Miranda Thompson, who normally works as a retail journalist but for a few hours on 29 August was a dancer in the Paralympic opening ceremony, was also one of the lucky few to secure a ticket to the parade in a ballot conducted among volunteers. "It's wonderful that they are honouring the volunteers, and quite a statement," she said.

It had been "lovely" to be in London during the Games period, she said, "to be in a different London. I hope people can carry on like that. I was getting annoyed with all the Olympic naysayers before, because I was convinced it was going to turn out to be amazing, and it has."

As for the parade, she said: "I'm just expecting to cry, really. I so hope it will capture how great London has been."

Oliver Poole, a pianist and student at the Royal College of Music who also took part in the Paralympic opening ceremony, said he had been "wildly inspired" by his experience.

"Lots of people say that London is going to go back to normal, but there's a lot we as a city have taken from this. To be part of the celebration parade is really the cherry on the cake."